Software Engineer

SIMON SOKA

11+ years building enterprise systems, from Mastercard’s payment infrastructure to customs administration at national scale.

Building software
that works at scale

0+ Years of experience
0 Companies
0 API requests/day shipped
0% Customs processing speedup

I'm a developer who's spent the better part of a decade deep in .NET ecosystems, building customs systems that process thousands of declarations daily, payment platforms that handle millions of transactions, and security solutions for physical infrastructure.

I care about clean architecture, test-driven development, and shipping software that people actually rely on.

Backend
C# ASP.NET Core .NET Framework Python GoLang Entity Framework Dapper RabbitMQ
Frontend
React Angular TypeScript WPF Razor Pages DevExpress
Data & DevOps
SQL Server MongoDB Redis Azure DevOps Node.js Microservices REST APIs TDD
Languages
English Slovak Russian

Where I've built things

2024 – Present

Evolved s.r.o.

Founder & Full-Stack Developer

  • Built and launched evolved.sk from scratch: React 19, TypeScript, Vite with custom SSR, Node.js + Express backend, MongoDB, and Redis
  • Integrated Stripe API (payments, webhooks, invoicing), Packeta shipping API, Heureka XML feed, and VATSense for EU tax rates
  • Set up infrastructure: Nginx reverse proxy with SSL/HTTP2, Cloudflare CDN, PM2 process management, Sentry error monitoring
  • Implemented security across the stack: JWT auth with httpOnly cookies, CSRF protection, rate limiting, input validation, XSS escaping
  • Handled SEO (structured data, SSR, sitemaps), GA4 + Ads conversion tracking, Microsoft Clarity, Google Merchant Center, and GDPR compliance
  • Managed marketing, content writing, social media, and paid advertising campaigns
  • Built chensconsulting.com for a client: Vercel deployment, Sanity CMS for content management, and Resend for transactional emails
  • Shipped full e-commerce platform solo: payments, shipping, invoicing, i18n (SK/EN), and analytics
  • Achieved Lighthouse performance score of 93-96 with SSR, lazy loading, and idle-until-urgent hydration
2023 – 2024

Ditec

Full-Stack .NET Developer · Remote

  • Collaborated with IT analysts to translate EU/national customs business logic into actionable plans for a critical government customs administration system upgrade for the Slovak Financial Administration
  • Designed and implemented real-time declaration tracking using RabbitMQ for asynchronous processing of customs data across import/export workflows
  • Optimized database interactions with Dapper and message queuing with RabbitMQ, improving overall customs clearance processing speed
  • Built complex desktop (WPF) interfaces using Prism and DevExpress for back-office customs operations
  • Modernized codebase with DryIoc dependency injection and strict unit testing (XUnit, Moq)
  • Presented the upgraded architecture and features to key stakeholders from the Slovak Financial Administration
  • Improved customs processing speed by 30%
  • Reduced asynchronous declaration processing time by 25% with real-time tracking
2022 – 2023

Mastercard

Full-Stack .NET Developer · Itera Slovakia · Remote

  • Developed and maintained core payment systems for Mastercard Payment Services Denmark, serving critical Danish financial infrastructure used by 95%+ of the population
  • Worked on Betalingsservice (consumer direct debit) and Leverandørservice (B2B payments) platforms, including API integrations and web portals
  • Built and optimized high-throughput REST APIs under Mastercard’s Golden Standards compliance framework
  • Delivered in a cross-border Scrum team (Slovakia, Denmark) using C#/.NET, ASP.NET Core, Razor Pages, Azure DevOps, and Azure Cloud
  • Built a fraud detection system reducing fraudulent transactions by 15%
  • Shipped an API handling 1M+ requests/day
2021 – 2022

CRIF

Full-Stack .NET Developer · CRIF Slovak Credit Bureau · Remote

  • Developed and enhanced Credit Navigator (CNAV), a secure web portal enabling electronic communication between financial institutions, municipalities, and banks for credit data access and tax enforcement
  • Built data visualization dashboards for credit reports from SRBI (Slovak Banking Credit Bureau) and NRKI registers, providing real-time financial insights to institutional clients
  • Optimized MSSQL database queries and Entity Framework data access layer, improving response times for credit report retrieval across 17+ banks
  • Maintained and improved ASP.NET MVC backend with RazorEngine templating and AngularJS frontend for server-side rendering of financial documents
2019 – 2021

Logamic

Software Engineer · Remote

  • Built software infrastructure for managing laboratory hardware in the U.S.
  • Focused on WPF, Prism, DevExpress, and TDD
  • Streamlined backend operations using Python and C
2015 – 2021

TSS Group

.NET Developer · Remote, Hybrid, On-site

  • Managed a team of 7 optimizing a high-traffic web application
  • Created a security platform for hotels and buildings using ASP.NET Core, GoLang, and Python
  • Worked with SOAP, WSDL, SATEL security protocols, and AI-based license plate recognition
2019 – 2021

Slovenská technická univerzita v Bratislave

Information Technology

  • Prioritized career growth, transitioning to full-time professional development
Certification

Oracle Certified Professional

Oracle Database Security Expert Certification

Let's work together

Have a project in mind or looking for a software engineer? I'd like to hear about it.